Blood-sucking arthropod saliva is a rich source of molecules that affect hemostasis,1 including vasodilators2,3 and inhibitors of blood coagulation4,5 and platelet aggregation.6-8 Among the platelet inhibitors, salivary lipocalins bind to and remove pro-aggregatory amines such as ADP, epinephrine, and serotonin,8-10 while RGD-containing peptides block integrin αIIβ3 interaction with fibrinogen.7 In addition, enzymes such as apyrases and lipid acethyl hydrolases degrade biologically active molecules such as ADP and PAF, respectively.11,12 Further, specific antagonists of collagen-induced platelet aggregation/adhesion have been found in salivary glands of ticks and other hematophagous animals, such as leeches.13-15 
Most salivary components have been identified through classical procedures where a given function was used to isolate an active molecule.1 Using sequence similarities, transcriptome and proteomics analyses have also been used to identify arthropod saliva compounds.16-19 For example, Ixolaris from Ixodes scapularis was initially identified by its sequence similarity to a tissue factor pathway inhibitor and has been found to have a potent anticoagulant activity in vitro5 and antithrombotic effects in vivo.20 Nevertheless, a large number of salivary gland transcript-encoded products have no similarity to proteins deposited in databases. Accordingly, annotation and functional assignment for these proteins has proven difficult.1 For example, the family of 30-kDa salivary allergens found in different blood-sucking arthropods, including Aedes sp,17 Culex sp,19 and Anopheles sp.16,18,21,22 While these proteins are major salivary components that display significant sequence similarity and many investigators have spent considerable effort, their function has remained elusive thus far.16-19,21,22 In this disclosure, it is shown that Aegyptin is a specific ligand or binding partner for collagen.
For all of the above reasons, it is important to identify antithrombogenic molecules, which block platelet adhesion, activation and aggregation.